Refrigeration



May 6,1930,

A. LENNING REFRIGERATION Filed May 21, 1929 2 Sheets-Sheet l v INVEN OR4/5 ATTORNEY y 6, 1930- A. LENNING 1,757,254

REFRIGERATION Filed May 21, 1929 2 Sheets-Shec 2 G Ha a \g w W x I I I ll f l I: ..l| l{' V I \Q Q I N] A I dlrwlNV NTOR m. BY '17- Patented May6, 1930 N. Y., RATION, OF NEW YORK, IN. Y.,

ALVAB LENNING, OF NEW YORK,

ASSIGNC JR TO ELECTROLUX SERVEL CORPO- A CORPORATION OF DELAWAREREFRIGERATION Application filed Kay 21,

My invention relates'to refrigeration and has for an object to provide asim 1e and stable systemof the type wherein a fluid is expelled fromsolution in a second fluid in the evaporator by the introduction of athird fluid into the evaporator.

Another object of the invention is to provide a novel refrigeratingsystem without moving parts and in which the evaporator can be situatedlower than the other parts of the system.

Further objects and the advantages of the present invention will beapparent from the ollowing description taken in conjunction with theaccompanying drawings showing diagrammatically refrigerating systemsembodying my invention of which:

Fig. 1 is a simplified diagrammatic showing of a refrigerating systemembodying the invention;

Fig. 2 shows the system equipped with heat exchangers and other details;and

Fig. 3 shows another embodiment of the invention.

The system of apparatus according tothe invention contains a first fluidherein called the expeller fluid, a second fluid in which the firstfluid is soluble herein called the solvent,

and a third fluid soluble in the second fluid ut not in the first fluidherein called the refrigerant. In describing the systems shown in thedrawings, I will select for purposes of illustration diethylamine as theexpeller fluid, water as the solvent and ammonia as the refrigerant, itbeing understood, however, that other combinations of fluids may be usedso long as they have the relative solubilities above outlined and arecapable of existing in the proper conditions within the system whichconditions will be hereinafter pointed out.

In Fig. 1 reference character 10 designates a generator which may beheated in any suitable way as by a gas flame or by an electric heatingelement. The generator containsa 1989 Serial No. 384,788.

solution of diethylamine in water. Diethylamine has a lower boilingpoint than water and is expelled from solution in the water in thegenerator. Diethylamine vapor passes through conduit 11 in which isinterposed .a rectifier 27 and into a condenser 12 which may be cooledin any suitable way as by a water jacket 13 or by air. In condenser 12the vapor is condensed into liquid and the liquid runs thl Fllllghconduit 14 into evaporator 15.

has been driven oflpasses through conduit 16 and into absorber 17.Absorber 17 is suitably cooled as by a coil 18 carryin running water.Absorber 17 is also supplie with ammonia gas through conduit 19connecting'the'absorber with the upper part of evaporator 15. Inabsorber 17 a solution of ammonia in water is formed. -Absorber 17 isarranged at a higher level than evaporator 15 and the solution ofammonia in water flows through conduit 20 and into evaporator 15. Theabsorber contains trays 24 over which the water cascades downwardly.

In the evaporator the diethylamine entering through conduit 14 forms asolution with the water thereby liberating more or less of the ammonia.his ammonia becomes gaseous and in so doing takes up heat from thesurroundings thus producing refrigeration. he gaseous ammonia flowsthrough conduit 19 to the absorber to be again absorbed and thus reducedto theliquid phase. The solution of diethylamine and water reformed inthe evaporator passes through conduit 21 and through a thermo-siphondevice 22and into generator 10. The pu ose of the thermo-siphon is tolift the liquid to permit a higher level in the generator than in theabsorber-evaporator cycle so that liquid may flow by gravity from thegenerator to the absorber through conduit 16.

An equalizing pipe 23 is provided connecting the upper part of absorber17 with the higher portion of conduit 14.

e water from which the diethylamine The present system is based. on theuasichemical interaction of two bases of di erent strengths and a weakacid or fluids acting as such. The expeller is the strongerbase; the

refrigerant is the weaker base and the solvent is the weak acid. In theexample above described, the strong base is the diethylamine;

is much greater than the heat of solution in water foroperatingconditions in the evapora-. tor. If diethylamine is added to asolution of ammonia in water, ammonia gas is liberated and acoolingefiect results. The amount of cold generated is equal to the sum of thelatent heat of vaporization of the ammonia plus the heat of solution ofammonia in water minus the heat of solution of diethylamine in water. 7The reason why thedisplacement of the ammonia by the diethylaminetakes-place v "isnot large enough to ofiset the vaporization of theammonia,

' reference to is that the heat of solution ofdiethylamine in water isgreater than the heat of solution of ammonia in water. However, the difierence latent heat of wherefore the net result will be a cooling efiect.Obviously the greater the heat of vaporization is with the differencebetween the heats j of solution the greater will be the cooling eftainthe same'fiuids as in Fi a the e aporator. p

. heat exchange relation with conduit 19 in orcontact of the fluids.

feet per unit weight of refrigerant liquid.

Instead of using two bases and one weak acid, a system of this type mayemploy two acids an one weak base.

g. 1. Like refer- 11ke parts in the 'ence characters designate H 16 andconduit 21 are two figures- Conduit arranged in heat exchange relationin order to; cool .wa'rm liquid leavingthe. generator- 2- throughconduit 16 by'the cool liquid leaving- Conduit 14 is arranged in der totransfer cold from the fluid leaving the evaporator 15 into the fluid inconduit 14. entering the evaporator. Trays or disks 24: and 34 may beprovided in the absorber and evaporator in order toobtain more intimateTrays 34 in the evaporator are formed with turned down edges around theapertures in the same to give liquid surfaces for release of gas. Theupper part of the evaporator in Fig. 2 acts as a gas sepa rator. Theliquid will substantially fill the evaporator whereas the absorbercarries liquid only on trays 24. I 1

It will be obvious that the parts'may be are ranged in a number of waysand that such decharacters in the various figures Fig. 2.

vices as the heat exchangers may be made in a number of forms. Auxiliarydevices may be added to the system to improve the efiiciency.

The system is hermeticall sealed and operates at the same pressurethroughout except for differences in pressure due to any heights ofliquids. Force for circulation of fluid is generated within the system.Circulationbetween the absorber and evaporator is produced bydifierences of specific gravity. Circulation between the enerator andthe .absorber-evaporatorcycl e is produced due to .changes in specificgravity caused by the. thermo-siphon member 22. The formation of gas inthe generator and condensation in thecondenser 12 causes the flow of thevapor of the expeller from the generator through 'the condenser and tothe evaporator.

Other combinations of flulds which may be used in this system are: (1)ethylaniine, water and ammonia; and (2 diethylamine,

boric acid dissolved in water, and methylamine. In; each of these groupsthe first mentioned is the expeller, the second mentioned is the solventand 'the third mentioned is the refrigerant.

In each case the expeller has a lower boiling.

point than the solvent and both the expeller and the solvent have ahigher boiling point than that of the refrigerant.

Thesystem shown in Fig. 3-islsimilar to that of Fig. 2, differing inshowing additional parts for obtaining higher eificiencv. Likecorresponding parts.

- Consider' g the same fluids as being used in Fig. 3 as in Fig. 1,diethylamine vapor is driven ofi in the generator and passes throughconduit 11 into a vertical separator 29, whence it passes throughconduit 11, in which rectifier 27 is interposed, and into"condenser12."v 1 Liquid diethylamine flows throughconduit '14 The arrangement shownin Fig. 2 may condesignate i into the evaporator as in the apparatus ofWater, generator through-conduit 16, passes through 31' and thencethrough conduit 16- into the from the absorber into. the evaporator tively large size and also conducts gaseous ammonia upwardly to theabsorber. A tube 33 receives the solution lower part of the evaporator.

The diethylamine solution leaves the evapweak in diethylamine, leavesthe I a jacket 30 surrounding a verticalseparator:

oratorthrough conduit 21'' and passes into I separator 31. In. separator31 further ammonia is given off due to its temperature being higher thanthat of the evaporator. fThe ammonia liberated in separator 31passesthrough conduit 36 into the absorber.

The diethylamine solution asses through conduit 21 where it is heate .bythe warmliquid in conduit .16. This drives some diconduit 11. Fromseparator'29, diethylamine solution passes through conduit 21 intoethylamine out of solution. This diethylamine vapor passes-up inseparator 29 and into thermo-siphon chamber 38 which is heated by aheating source projected into flue 39..

The solution is lifted through siphon pipe 40 into the main generatorchamber 41 also heated by flue 39. I a,

In the various embodiments the evaporator or a part thereof can besituated below the remaining parts which facilitates mount- ,ingvtherefrigerator on the top of a cabinet.

, hat I claim is:

combination, a condenser, an absorber, an evaporator, means tosupply'the eva orator with a solution from the absorber'an a con? densedfluid from the condenser, means to conduct vapor from the evaporator totheabsorber and means for receivingsolution from the evaporator,separating the same and condenser and erated within the system.

I 7. That improvement in the art of refrig I by the aid of an absorptionsystem including a generator, a condenser, an absorber and anfjsystemincluding a generator, acondenser, an

- evaporator which comprises expelling a first conducting gaseous fluidto the liquid to the absorber. I 2. The process of producingrefrigeration fluid from solution in asecond fluid in the generator,conducting the firstrfluid tothe condenser and liquefying the same,conductorator to recombine the first and second fluids .ond'fiuids tothe generatormqf I I 3. Refrlgeratmg apparatusqco' prising- 31generator, a condenser, an absorberand'an generator, a condenser, anabsorber, an Pif'e vaporator Which comprises expelling dietha *ylaminefrom solution in water, conducting the diethylamine vapor to thecondenser and condensing the vapor toliquid, conduct-ing ing the secondfluid'into the presence of a third fluid in gaseous form in theabsorber'thereby forming a solution, conducting the last-mentioned solution tothe evaporator, conducting the liquefied first fluid to the evapandliberate thethird fluid asa gas, return- I ing the gaseous third fluidto the absorber. "and returning the recombined first andsecorator, saidabsorber being situated at a high er level than the evaporator, means toIconduct vapor from :the generator to theflcondenser, means .to conductliquid from the condenser to the evaporator, means to coniv v ductliquid from the generator to the absorb- 5 5O er, means to conductliquid. from the absorber to the evaporator and means to conduct liquidfrom'the evaporator tohthe-gen erator. I V

4. Refrigerating apparatus comprising a generator, a condenser, anevaporator, a consaid connection, a connection for flow of gase- 'ousfluid from said generator to said condenser, a connection for flow ofliquid from said condenser-to said evaporator, means to conduct liquidfromsaid evaporator tosaid gen 2 erator and means to conduct vaporfromsaidevaporator to said absorber. I 5. That improvement in'the art ofrefrigerxdenser. I v a -6. 'That improvement in the art-of 'refrigeration through the agency of an absorption Y 1. Refrigerating apparatuscomprising, in

ating thro ughthe agency of an absorption I system including agenerator,- a condenser,

an absorber and an evaporator which con zf ,sists in conducting fluidfrom both the en-- J erator and. the evaporator to the absor er, forminga solution in the'absorber, conductdenser to the evaporator, conductingliquid ducting, gas from the generator -to the consystem including agenerator, a condenser, an a sorber and an evaporator'which consists inconducting fluid from both the generator and the evaporator to theabsorber, formin a so--. lution in the absorber, conducting flui fromevaporator, conducting liquid from the evaplorator to the generator, theenerator to the condenser and circulating uids within the system due toforce generation through the agency of an absorptionabsorber and anevaporatorwhich'consists' fromthe evaporator to the generator and con Iboth" the absorber and the condenser to the Y conducting gas from inconducting fluid from both the generator 7.

and the evaporator to the absorber, forming a from both the absorber andthe condenser to the evaporator, conducting liquid from the evaporatorto the generator, conducting gas from the generator to the condenser andcirculating the fluids within the system due to solution in theabsorber, conducting fluid 'force generated within the system whilemaintaining a substantially constant pressure I throughout the system. I1

-8. he process of producing refrigeration the water into the presenceof'ga seou s" am-' r monia in the absorber thereby forming 'a so' f" jlution, conducting the solution'of ammonia and water to the evaporator,conducti-ng the liquid diethylamine to the evaporator to'form a-solutionwith the water and thereby liberatl ing gaseous ammonia, returning thegaseous I I ammonia to the abso'rberand returning the a.

hylamine and water solution tothe g eratorj x I 9. Refrigerating 1apparatus c t'nnprising 'a generator; av first 'separator, '.avaporconnec- I 105 by the aid of an absorption system including.

a second separator, means to conduct liquid from the evaporator to thesecond separator, a connection between said second separator and saidabsorber, a connection between the lower partof the first separator:mdthe generator, a connection between the separators and means toconduct liquid'from the generator, in heat exchange relation with thelast-mentioned connection, in heat exchange relation with the secondseparator and into the absorber. In testimony whereof I have afiixed mysignature.

ALVAR LENNIN G.

